四川壤塘县茸郎沟泥石流发育特征及危险性

Debris Flow Development Characteristics and Risks of Ronglang Gully in Xiangtang County, Sichuan Province

通过对四川壤塘县茸郎沟泥石流实地勘查,从地形、物源及水源查明其发育特征,并根据雨洪法获得泥石流流速、流量等运动学参数。采用CFD软件ANSYSCFX计算模拟茸郎沟20a与50a一遇泥石流运动、堆积过程,获得流速及流量等动力学参数变化特征与危险区范围。模拟结果显示,20a一遇泥石流与50a一遇泥石流通过堆积区的平均速度分别为为4.30m/s、4.78m/s,最大冲淤泛滥区范围占居民区面积的67%、79%,会对位于堆积区的居民构成严重危害。

Through the field investigation of Ronglang gully in Xiangtang County, Sichuan province, development characteristics are identified from topography, provenances and headwaters, and the kinematic parameters of the debris flow such as velocity and flow rate are determined according to the rain-flood method. The ANSYS CFX of CFD software was used to calculate and simulate the movement and accumulation process of Ronglang debris flow with a frequency of 20 years and 50 years to obtain the dynamic characteristics of the flow parameters such as velocity and flow rate as well as the range of the risk area. The simulation results show that the average velocity of debris flow with a frequency of 20 years and 50 years passing through the accumulation area are 4.30m/s and 4.78m/s respectively, and the maximum flooding areas account for 67% and 79% of the residential area respectively, which will cause serious hazards to the residents in the accumulation area.